بهبود عملکرد روغن و اسیدهای چرب روغن دانه ارقام مختلف کنجد (.sesamum indicum l) با محلول‌‏پاشی گوگرد

رویکرد جهانی در تولید گیاهان روغنی به سمت افزایش عملکرد روغن و تغییر نسبت اسیدهای چرب روغن دانه از طریق روش‌های مدیریتی نظیر مصرف بهینه کودهای شیمیایی می‌باشد; بنابراین بهبود محتوای روغن و اسیدهای چرب روغن دانه ارقام مختلف کنجد با محلول‏پاشی گوگرد، هدف اصلی این پژوهش بود. این پژوهش به‌صورت آزمایش فاکتوریل در قالب طرح بلوک‏های کامل تصادفی با سه تکرار در سال‏های 1397 و 1398 در شهرستان فسا، واقع در شرق استان فارس انجام شد. فاکتور اول پنج رقم کنجد (شامل داراب، فسا، عراقی، دشتستان و برازجان) و فاکتور دوم محلول‌پاشی گوگرد در پنج غلظت (شامل شاهد، 2، 4، 6 و 8 گرم در لیتر) بود. در این آزمایش درصد پروتئین و روغن دانه کنجد، عملکرد دانه و روغن دانه و اسیدهای چرب آن اندازه‌گیری شد. نتایج نشان داد که افزایش غلظت گوگرد با غلظت 8 گرم در لیتر سبب افزایش 13.4 درصدی روغن دانه نسبت به شاهد گردید. مصرف گوگرد با غلظت 8 گرم در لیتر سبب کاهش 19.1 درصدی پروتئین دانه نسبت به شاهد گردید. نتایج حاصل نشان‌دهنده پاسخ متفاوت ارقام از نظر میزان عملکرد روغن و اسیدهای چرب روغن دانه بود. اسید‏های چرب غیراشباع اولئیک اسید و لینولئیک اسید (با غلظت 44.4 و 36.8 درصد و اسیدهای چرب اشباع پالمتیک اسید و استئاریک اسید با غلظت 9.6 و 7.2 درصد، بیش‌ترین میزان را در ارقام مختلف کنجد موردمطالعه نشان دادند. با افزایش سطح گوگرد مقدار اسیدهای چرب موردبررسی به استثنای لینولئیک اسید در دانه افزایش یافت. در مجموع نتایج نشان داد که استفاده از غلظت محلول‌پاشی 8 گرم در لیتر گوگرد باعث افزایش عملکرد روغن و اسیدهای چرب روغن دانه ارقام مختلف کنجد می‌‏گردد.

improving grain oil yield and oil fatty acids of different sesame (sesamum indicum l.) cultivars with sulfur spraying

the global approach in the production of oil plants is to increase oil yield and change the proportion of fatty acids in seed oil through management methods such as optimal use of chemical fertilizers; therefore, the main goal of this research was to improve the content of oil and fatty acids in the seed oil of different sesame cultivars with sulfur foliar application. this research was conducted as a factorial experiment in the form of randomized complete block design with three replications in 2018 and 2019 in fasa city, located in the east of fars province, iran. the first factor was five sesame cultivars (including darab, fasa, iraqi, dashestan and barazjan) and the second factor was sulfur spraying in five concentrations (including control, 2, 4, 6 and 8 grams per liter). in this experiment, the percentage of sesame seed oil and protein, seed yield, seed oil and its fatty acids were measured. the results showed that increasing the concentration of sulfur with a concentration of 8 grams per liter caused a 13.4% increase in seed oil compared to the control. consumption of sulfur with a concentration of 8 grams per liter caused a decrease of 19.1% in grain protein compared to the control. the results showed the different response of cultivars in terms of oil yield and fatty acids of seed oil. unsaturated fatty acids, oleic acid and linoleic acid (with a concentration of 44.4 and 36.8 percent and saturated fatty acids palmitic acid and stearic acid with a concentration of 9.6 and 7.2 percent, are the highest in different sesame cultivars) study showed. with the increase of sulfur level, the amount of fatty acids investigated increased in the seed, except for linoleic acid. in total, the results showed that the use of foliar spraying concentration of 8 grams per liter of sulfur increased the yield of oil and fatty acids of seed oil of different sesame cultivars.introductionsesame (sesamumn indicum l.) is one of the plants adapted to arid and semi-arid regions of the world. sesame planting has been customary since ancient times, and features such as tolerance to drought and high quantity and quality of oil are among the things that have drawn attention to this plant. sesame is widely used in the preparation of edible oil and medicine due to its quality oil, protein and antioxidants. consumption of sulfur increases the yield of sesame. native populations can be used as a valuable genetic resource in breeding new cultivars if they have suitable traits. the present research was aimed at evaluating the effect of foliar application of different concentrations of sulfur on the improvement of oil yield (quantity of oil yield) and fatty acids of seed oil (quality of oil yield) in different sesame cultivars.materials and methodsthis research was conducted as a factorial experiment in the form of randomized complete block design with three replications in 2018 and 2019 in fasa city, located in the east of fars province, iran. the first factor was five sesame cultivars (including darab, fasa, iraqi, dashestan and barazjan) and the second factor was sulfur spraying in five concentrations (including control, 2, 4, 6 and 8 grams per liter). sulfur was used as a liquid suspension with the brand name of sulfur samiran. in this experiment, the percentage of sesame seed oil and protein, seed yield, seed oil and its fatty acids were measured. results and discussionin all concentrations of sulfur application, the highest oil yield was observed in dashtestan cultivar, while the lowest oil yield was observed in iraqi cultivar. in all cultivars, with the increase in sulfur concentration, the oil yield of sesame cultivars increased significantly, so that the foliar spraying concentration of 8 grams per liter of sulfur caused a 24% and 28% increase in oil yield in darab and fasa cultivars, respectively. an increase of 13, 17 and 24% in oil yield in iraqi, dashtistan and barazjan cultivars, respectively, was achieved with foliar spraying of 8 grams per liter of sulfur. 11 fatty acids including four saturated fatty acids (myristic acid, palmitic acid, margaric acid and stearic acid) and 7 unsaturated fatty acids (palmitoleic acid, heptadecanoic acid, oleic acid, linoleic acid, alpha linoleic acid, arachidonic acid and gadoleic acid) was recognized from the investigated sesame cultivars. conclusionin this experiment, sulfur had a positive contribution in bringing sesame closer to oil yield potential and seed oil quality. in all cultivars, the highest increase in the percentage of fatty acids obtained by applying foliar application of 8 grams per liter of sulfur fertilizer, which belongs to arachidonic acid. this unsaturated fatty acid increased by 17.2% compared to the control treatment with increasing concentration of sulfur spraying. the highest yield of sesame seed oil was obtained with foliar spraying of 8 grams per liter of sulfur in the dashtestan cultivar at the rate of 1504 kg per hectare.